The present invention relates broadly to closures for containers and more particularly to a locking stopper made of a resilient material such as rubber or other elastomer.
These closures are typically used on containers for pharmaceutical products. Typically the closure or stopper comprises a body portion having a depending plug portion which snugly engages in the mouth of the container and an enlarged radially directed outer flange portion which seats on the axial end face of the bottle defining the discharge opening therein. When applying or removing the stoppers manually from the container (such as a bottle), generally it cannot be avoided that in grasping the parts of the locking stopper directly adjacent to the mouth edge of the bottle, the fingers also contact the edge of the bottle. This contact presents the danger of contaminating the contents of the container such as rinsing solutions, infusion solutions and the like, which must be maintained sterile. Moreover it has been found that these stoppers are difficult to assemble and remove especially when they have been firmly inserted in place.
With the above in mind, it is an object of the present invention to provide a stopper assembly of the above mentioned type which is easy to handle and wherein the finger contact with the stopper parts directly adjacent to the bottle edge in the assembled position can be avoided. This is achieved in accordance with the present invention by providing a stopper assembly including a gripping element or pull ring in the area of the outer lid side or top face of the stopper which can be advantageously grasped by the user so that direct finger contact of the actual stopper is prevented thereby obviating the dangers of contamination of the container contents.
The gripping element is formed by a gripping handle or the like connected with the locking stopper and formed preferably in the form of a gripping ring. The gripping element is adapted to be actuated easily from its initial seated position flush with the top face of the stopper to an operative erect position engageable by a finger of the user to unseat the stopper from the container when desired. The gripping element and the stopper are preferably made in two parts which can be locked together so that the stopper has a connecting part for the gripping element and this has a connecting piece which can be connected with the stopper. This facilitates a production of the assembly in a very simple manner and there is also the advantage that the gripping element and stopper can each be made from different materials which are each adapted to their objectives.
In accordance with the preferred embodiment of the invention, the stopper has an annular groove with an undercut or the like which opens outwardly towards the outer top face thereof within which an annular connecting piece of the gripping element tightly engages in a snap fit or the like. Besides the fact that this can be simply produced, a comparatively large connecting area is provided as a result of this construction so that undesired separation of the connection is prevented even when a stopper is firmly seated in a bottle opening.
The gripping element comprises an insert ring or the like preferably provided with an abutting flange, the ring having a circumferentially extending barbed projection interacting and engaging with the undercut or the like in the annular groove. This gripping element is also capable of being manufactured and produced rather economically. The abutting flange is directed approximately radially outwardly and forms a support rim for a locking member or the like which can be screwed or crimped over the stopper.
The undercut is preferably provided on the radially inner side of the groove and the wall of the insert ring is tapered at its inserting end to facilitate assembly. The groove defining part determines the shape in this case of the counter connecting piece which is connected with the gripping element. Assembly of the locking stopper in the groove can be simplified by the somewhat tapered form of the inserting end of the insert ring.
A further feature of the present invention is the arrangement wherein the gripping ring is connected with the insert ring preferably by an elastic pivot and is located in the initial position approximately concentrically with the insert ring. In other words, in the initial position the gripping element lies in a plane flush with the top face of the stopper and there is no interfering projection of the gripping element. On the other hand, when it is desired to remove the stopper, the gripping element can be easily raised without problems as a result of the elastic pivoting arrangement and then the fingers of the user may be inserted in the gripping ring.
The insert ring and the abutting flange are preferably made of an inherently stable material such as plastic. The gripping element has a good inherent stability as a result of this construction and also permits the transmission of greater removal forces by the user. Moreover, the holding pressure exerted on the stopper by an additional screw cap or the like used to seat the stopper assembly on the container can be easily transmitted further via the somewhat more inherently stable gripping element. In accordance with the present invention, the gripping ring is disposed within the abutting flange plane in its initial position and is preferably unilaterally connected with this abutting flange by at least one connecting hinge or cross piece. By this arrangement the gripping ring and also the gripping element as a whole does not interferingly project beyond the outline of the stopper. As a result, accidental removal of the stopper from the bottle opening, for example, by snagging and other reasons, is prevented. In large diameter stoppers, the gripping ring may be connected to the abutting flange by several connecting hinges. Specifically two diametrically opposed connecting bridges or cross pieces can be provided so that in this instance two semi-circular rings are formed which arch upwards towards each other to allow insertion of a finger in the rings. In this case, a substantially symmetrical removal force is produced upon movement of the stopper in a direction to remove it .